/*! \file shr_pb.c
 *
 * Dynamic print buffer support.
 */
/*
 * Copyright: (c) 2018 Broadcom. All Rights Reserved. "Broadcom" refers to 
 * Broadcom Limited and/or its subsidiaries.
 * 
 * Broadcom Switch Software License
 * 
 * This license governs the use of the accompanying Broadcom software. Your 
 * use of the software indicates your acceptance of the terms and conditions 
 * of this license. If you do not agree to the terms and conditions of this 
 * license, do not use the software.
 * 1. Definitions
 *    "Licensor" means any person or entity that distributes its Work.
 *    "Software" means the original work of authorship made available under 
 *    this license.
 *    "Work" means the Software and any additions to or derivative works of 
 *    the Software that are made available under this license.
 *    The terms "reproduce," "reproduction," "derivative works," and 
 *    "distribution" have the meaning as provided under U.S. copyright law.
 *    Works, including the Software, are "made available" under this license 
 *    by including in or with the Work either (a) a copyright notice 
 *    referencing the applicability of this license to the Work, or (b) a copy 
 *    of this license.
 * 2. Grant of Copyright License
 *    Subject to the terms and conditions of this license, each Licensor 
 *    grants to you a perpetual, worldwide, non-exclusive, and royalty-free 
 *    copyright license to reproduce, prepare derivative works of, publicly 
 *    display, publicly perform, sublicense and distribute its Work and any 
 *    resulting derivative works in any form.
 * 3. Grant of Patent License
 *    Subject to the terms and conditions of this license, each Licensor 
 *    grants to you a perpetual, worldwide, non-exclusive, and royalty-free 
 *    patent license to make, have made, use, offer to sell, sell, import, and 
 *    otherwise transfer its Work, in whole or in part. This patent license 
 *    applies only to the patent claims licensable by Licensor that would be 
 *    infringed by Licensor's Work (or portion thereof) individually and 
 *    excluding any combinations with any other materials or technology.
 *    If you institute patent litigation against any Licensor (including a 
 *    cross-claim or counterclaim in a lawsuit) to enforce any patents that 
 *    you allege are infringed by any Work, then your patent license from such 
 *    Licensor to the Work shall terminate as of the date such litigation is 
 *    filed.
 * 4. Redistribution
 *    You may reproduce or distribute the Work only if (a) you do so under 
 *    this License, (b) you include a complete copy of this License with your 
 *    distribution, and (c) you retain without modification any copyright, 
 *    patent, trademark, or attribution notices that are present in the Work.
 * 5. Derivative Works
 *    You may specify that additional or different terms apply to the use, 
 *    reproduction, and distribution of your derivative works of the Work 
 *    ("Your Terms") only if (a) Your Terms provide that the limitations of 
 *    Section 7 apply to your derivative works, and (b) you identify the 
 *    specific derivative works that are subject to Your Terms. 
 *    Notwithstanding Your Terms, this license (including the redistribution 
 *    requirements in Section 4) will continue to apply to the Work itself.
 * 6. Trademarks
 *    This license does not grant any rights to use any Licensor's or its 
 *    affiliates' names, logos, or trademarks, except as necessary to 
 *    reproduce the notices described in this license.
 * 7. Limitations
 *    Platform. The Work and any derivative works thereof may only be used, or 
 *    intended for use, with a Broadcom switch integrated circuit.
 *    No Reverse Engineering. You will not use the Work to disassemble, 
 *    reverse engineer, decompile, or attempt to ascertain the underlying 
 *    technology of a Broadcom switch integrated circuit.
 * 8. Termination
 *    If you violate any term of this license, then your rights under this 
 *    license (including the license grants of Sections 2 and 3) will 
 *    terminate immediately.
 * 9. Disclaimer of Warranty
 *    THE WORK IS PROVIDED "AS IS" WITHOUT WARRANTIES OR CONDITIONS OF ANY 
 *    KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WARRANTIES OR CONDITIONS OF 
 *    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE OR 
 *    NON-INFRINGEMENT. YOU BEAR THE RISK OF UNDERTAKING ANY ACTIVITIES UNDER 
 *    THIS LICENSE. SOME STATES' CONSUMER LAWS DO NOT ALLOW EXCLUSION OF AN 
 *    IMPLIED WARRANTY, SO THIS DISCLAIMER MAY NOT APPLY TO YOU.
 * 10. Limitation of Liability
 *    EXCEPT AS PROHIBITED BY APPLICABLE LAW, IN NO EVENT AND UNDER NO LEGAL 
 *    THEORY, WHETHER IN TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE 
 *    SHALL ANY LICENSOR BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY DIRECT, 
 *    INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF 
 *    OR RELATED TO THIS LICENSE, THE USE OR INABILITY TO USE THE WORK 
 *    (INCLUDING BUT NOT LIMITED TO LOSS OF GOODWILL, BUSINESS INTERRUPTION, 
 *    LOST PROFITS OR DATA, COMPUTER FAILURE OR MALFUNCTION, OR ANY OTHER 
 *    COMMERCIAL DAMAGES OR LOSSES), EVEN IF THE LICENSOR HAS BEEN ADVISED OF 
 *    THE POSSIBILITY OF SUCH DAMAGES.
 */

#include <sal/sal_libc.h>
#include <sal/sal_alloc.h>

#include <shr/shr_pb.h>

static int chunk_size = SHR_PB_CHUNK_SIZE_DEFAULT;

shr_pb_t *
shr_pb_create(void)
{
    shr_pb_t *pb;

    pb = sal_alloc(sizeof(shr_pb_t), "shrPbObj");
    if (pb) {
        sal_memset(pb, 0, sizeof(*pb));
        pb->bufsz = chunk_size;
        pb->buf = sal_alloc(pb->bufsz, "shrPbBuf");
        if (pb->buf) {
            /* Start with an empty string */
            *pb->buf = 0;
        } else {
            shr_pb_destroy(pb);
            pb = NULL;
        }
    }
    return pb;
}

void
shr_pb_destroy(shr_pb_t *pb)
{
    if (pb) {
        if (pb->buf) {
            sal_free(pb->buf);
        }
        sal_free(pb);
    }
}

int
shr_pb_printf(shr_pb_t *pb, const char *fmt, ...)
{
    va_list ap;
    char *buf;
    int len;
    int rv;

    if (!pb) {
        return -1;
    }
    if (!pb->buf) {
        return -1;
    }
    if (pb->len >= pb->bufsz) {
        return -1;
    }

    /* Try printf with existing buffer */
    va_start(ap, fmt);
    rv = sal_vsnprintf(&pb->buf[pb->len], pb->bufsz - pb->len, fmt, ap);
    va_end(ap);
    if (rv < 0) {
        return -1;
    }

    /* Check if the entire string fits */
    len = rv + pb->len;
    if (len >= pb->bufsz) {
        /* If not, then allocate a larger buffer */
        do {
            pb->bufsz += chunk_size;
        } while (len >= pb->bufsz);
        buf = sal_alloc(pb->bufsz, "shrPbBuf");
        if (!buf) {
            return -1;
        }
        /* Move current string to new buffer */
        sal_memcpy(buf, pb->buf, pb->len);
        sal_free(pb->buf);
        pb->buf = buf;
        /* Do printf again with the larger buffer */
        va_start(ap, fmt);
        rv = sal_vsnprintf(&pb->buf[pb->len], pb->bufsz - pb->len, fmt, ap);
        va_end(ap);
        if (rv < 0) {
            return -1;
        }
    }
    pb->len += rv;

    return rv;
}

int
shr_pb_mark(shr_pb_t *pb, int offs)
{
    if (pb) {
        if (offs < 0 || offs > pb->len) {
            offs = pb->len;
        }
        pb->mark = offs;
    }
    return offs;
}

void
shr_pb_reset(shr_pb_t *pb)
{
    if (pb) {
        if (pb->mark <= pb->len) {
            pb->len = pb->mark;
        }
        if (pb->buf) {
            pb->buf[pb->len] = 0;
        }
    }
}

const char *
shr_pb_str(shr_pb_t *pb)
{
    if (!pb || !pb->buf) {
        return SHR_PB_ERR_STR;
    }
    return pb->buf;
}

int
shr_pb_chunk_size(int csize)
{
    if (csize < 0) {
        chunk_size = SHR_PB_CHUNK_SIZE_DEFAULT;
    } else if (csize >= SHR_PB_CHUNK_SIZE_MIN && csize <= SHR_PB_CHUNK_SIZE_MAX) {
        chunk_size = csize;
    }
    return chunk_size;
}
